A press-fit terminal is press-fitted into a through hole of a circuit board so that electrical connection with the through hole is established by contact pressure. That is, soldering is not required for electrical connection between the press-fit terminal and the circuit board.
For this reason, a press-fit terminal has attracted attention as a contributor to simplification of processes for mounting a component such as a connector having a terminal on a circuit board, achievement of a lead-free state, or miniaturization of terminal arrangement on a circuit board by shortening the distance between the terminals.
For these reasons, it is important for a press-fit terminal to realize reliable electrical connection with a through hole of a substrate and obtain retention stability by a circuit board when press-fitted into the through hole.
Proposals to improve the retention stability of a press-fit terminal press-fitted into a through hole are also applied to a press-fit terminal in the form of a needle eye in which a slit facilitating deformation of the press-fit terminal in the through hole is formed in the press-fit portion.
In one of press-fit terminals in the form of a needle eye of a conventional example according to such proposals, the intermediate position of the slit in the press-fit direction of the press-fit terminal with respect to the through hole is displaced to the tip side of the press-fit terminal in comparison with the position where the width of the press-fit portion having a larger width than the hole diameter of the through hole becomes largest (see JP 4030129 B2).
In the press-fit terminal of the conventional example, the width between the contour of the press-fit portion and the slit is narrowed on the tip side of the press-fit terminal and widened on the base side by displacing the slit of the press-fit portion to the tip side of the press-fit terminal.
For this reason, on the tip side of the press-fit terminal where the width between the contour of the press-fit portion and the slit is narrowed, the rigidity of the press-fit portion is lowered, deformation toward the slit is facilitated, and it is possible to reduce the insertion force of the press-fit terminal for press-fitting the press-fit terminal into the through hole.
On the other hand, on the base side of the press-fit terminal where the width between the contour of the press-fit portion and the slit is widened, the rigidity of the press-fit portion is raised to lower the possibility of deformation toward the slit, and the possibility that the press-fit terminal buckles when press-fitting the press-fit terminal into the through hole, and it is possible to retain the press-fit terminal press-fitted into the through hole stably on the circuit board.